Venous thromboembolisms commonly begin in leg veins, and taller people tend to have long legs. Doctors speculate that taller people may be at higher risk for clots because the blood in their legs is struggling against the pull of gravity as it flows back to the heart.
“When blood is sitting still, it likes to clot,” said Mary Cushman, M.D., professor of medicine at the Larner College of Medicine at the University of Vermont, and director of the Thrombosis and Hemostasis Program at the University of Vermont Medical Center. “The slower the flow and the more turbulent the flow is, the more likely the blood is to clot.”
Height reduction is obviously not an option for preventing the condition, leaving tall people to educate themselves about the condition and its symptoms and risks, experts said. Obesity increases the possibility of a venous thromboembolism, for example. Cushman suggested that maintaining a healthy weight may be even more important for taller people.
A family history of blood clots also increases risk, she said. That’s why it’s especially critical for taller people to learn their family history and discuss it with their doctors.
Inactivity is another risk factor. Cushman said that tall people facing stretches of immobility or long plane rides should discuss the condition with their doctors, and consider options such as taking a low-dose aspirin to prevent clotting.
Cushman hopes the study will not only highlight the connection between height and venous thromboembolism but also spark an overall discussion about the condition. She noted that many people—regardless of their height—don’t know about venous thromboembolism, which causes symptoms such as pain, aching, swelling and redness in the legs, although if the clot travels to the lungs, patients may have difficult and painful breathing.
“So many of my patients come in with serious and even life-threatening blood clots and have never even heard of the condition,” said Cushman.